CN101270716A - Ignition modules for light duty internal combustion engines - Google Patents

Abstract

A capacitive discharge ignition (CDI) system that can be used with a variety of light-duty internal combustion engines, including those typically employed by lawn, garden, and other outdoor equipment. According to one embodiment, the CDI system includes an ignition module having a first switching device that shorts a charge coil during an initial portion of a charge cycle. Subsequently, the first switching device is turned 'off' so that a flyback charging technique charges an ignition capacitor. A second switching device is then used to discharge the ignition capacitor and initiate the combustion process.

Description

Ignition modules for light duty internal combustion engines

References to concurrent applications

This application claims priority to US Provisional Application Serial No. 60/897,565, filed January 26, 2007, which is hereby incorporated by reference in its entirety.

technical field

The present invention relates generally to ignition modules, and more particularly to ignition modules for capacitor discharge ignition (CDI) systems, such as those used in lawn, garden and other outdoor equipment.

Background technique

Capacitor discharge ignition (CDI) systems are sometimes used in small engines including, for example, light duty internal combustion engines used in lawn, garden and other outdoor equipment. To provide sufficient ignition voltage during low speed operation, some CDI systems employ charging coils with higher inductance and impedance characteristics. While such an arrangement may be beneficial for the engine to generate high voltage at lower engine speeds, it may hinder the ability of the CDI system to energize the electronics at higher engine speeds.

Contents of the invention

According to one aspect, an ignition module for a capacitive discharge ignition (CDI) system is provided. The ignition module includes: a charging coil, an ignition capacitor, a first switching device, a second switching device, and an electronic processing device coupled to the first and second switching devices. Activation of the first switching means creates a low impedance path between the charging coil and ground.

According to another aspect, a method of operating an ignition module is provided. The method comprises the steps of: (a) inducing electrical energy in a charging coil, (b) short-circuiting the charging coil during a first phase of the charging cycle, (c) interrupting the short circuit during a second phase of the charging cycle, (d) according to Flyback charging technology charges the ignition capacitor.

Description of drawings

Preferred exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals indicate like elements, wherein:

1 is a cross-sectional view showing portions of an exemplary capacitive discharge ignition (CDI) system for a light-duty internal combustion engine;

FIG. 2 is a schematic circuit diagram of an exemplary ignition module for the ignition system of FIG. 1;

FIG. 3 is a flowchart illustrating some steps of an exemplary method performed by the ignition module of FIG. 2;

4A-E are timing diagrams of various exemplary signals used during the method described in FIG. 3;

5 is a schematic circuit diagram of yet another exemplary ignition module for the ignition system of FIG. 1 , wherein the embodiment further includes a current sensing feedback feature;

6 is a schematic circuit diagram of yet another exemplary ignition module for use in the ignition system of FIG. 1 , wherein this embodiment further includes additional electronics that may also be energized by the charging coil;

Figure 7 is a graph showing high voltage spark ignition output over a wide range of engine speeds, where the graph compares a light duty internal combustion engine with an embodiment of the ignition module described herein to a comparable engine with a conventional ignition module Compare.

Detailed ways

The exemplary ignition system described herein is a capacitor discharge ignition (CDI) system that can be used with a variety of light duty internal combustion engines, including those commonly used on lawns, gardens, and other outdoor equipment. According to one embodiment, the ignition system uses ignition modules and "regression" charging techniques in a manner that can provide multiple positive features. For example, the ignition system can use a single charging coil to charge the ignition capacitor and additional electronic devices, it can charge in a wide spectrum of engine speed range, it can excite high voltage and high current devices at the same time, it can reduce the number of parts, There are many possibilities for weight and cost, so I won't list them here.

Ignition system

1, there is shown a cross-sectional view of an exemplary capacitive discharge ignition (CDI) system 10 interacting with a flywheel 12, which generally includes an ignition module 14 for electrically coupling the ignition modules Ignition leads 16 to spark plugs (not shown), and electrical connections 18 for coupling the ignition module to one or more additional electronic devices such as fuel control solenoids. Flywheel 12 is a weighted disc member coupled to crankshaft 30 for rotation under excitation of the engine. By utilizing its rotational inertia, the flywheel dampens fluctuations in engine speed to provide a more stable and uniform output. The flywheel 12 shown here includes a pair of magnetic poles or elements 32 disposed towards the periphery of the flywheel. Once the flywheel 12 rotates, the magnetic element 32 rotates through and electromagnetically interacts with various windings in the ignition module 14, as is known in the art.

The ignition module 14 is capable of generating, storing, and utilizing electrical energy induced by the rotation of the magnetic element 32 to perform various functions. According to one embodiment, the ignition module 14 includes a lamstack 40 , a charge coil 42 , a trigger coil 44 , an ignition circuit 46 , a step-up transformer 48 and an ignition module housing 50 . Lamination 40 is preferably a ferromagnetic component consisting of a stack of flat, magnetically permeable laminated sheets, typically made of iron or steel. The laminations help concentrate or concentrate the changing magnetic flux generated by the rotation of the magnetic element 32 on the flywheel. According to the embodiment shown here, lamination 40 has a generally U-shaped configuration including a pair of legs 60 and 62 . Post 60 is aligned along the central axis of charge coil 42 and post 62 is aligned along the central axes of trigger coil 44 and transformer 48 . When struts 60 and 62 are aligned with magnetic element 32 , which occurs at a particular rotational position of flywheel 12 , a closed-loop magnetic path including laminations 40 and magnetic element 32 is created. As two possibilities, the magnetic element 32 can be realized as part of the same magnet or as a plurality of separate magnetic components coupled together to provide a single magnetic path through the flywheel 12 . Additional magnetic elements may be added at other locations around the periphery of the flywheel 12 to provide additional electromagnetic interaction to the ignition module 14 .

Charging coil 42 generates electrical energy that can be utilized by ignition module 14 for a variety of different purposes including charging an ignition capacitor and energizing electronic processing devices, as two examples. The charging coil 42 includes a former 64 and a winding 66 and, according to one embodiment, is designed to have a relatively low inductance of about 2-10 mH and a relatively low resistance of about 10-50Ω. In order to achieve the above electrical characteristics, the winding 66 can be made of 30-34 gauge copper wire with 500-1500 turns. For reference, some prior art windings are made with about 3000 turns of 38 gauge wire, have an inductance of about 30-100 mH, and a resistance of about 150-400Ω. The electrical characteristics of a particular winding are usually tailored to its specific application. For example, charging coils that are desired to generate high voltages typically have more turns of finer gauge wire (and thus higher inductance and resistance) so that the charging coils can generate sufficient voltage during start-up or other low engine speeds. Conversely, charging coils designed to deliver high current typically have fewer turns of larger gauge wire (with correspondingly smaller inductance and resistance) so that when the engine is running at wide open throttle or other high engine speed conditions Charging coils are more efficient at generating high currents. As will be described in detail below, the charging coil 42 serves as a general purpose coil sufficient to simultaneously generate high voltage and high current, and capable of simultaneously generating high voltage and high current over a wide range of engine speeds.

Trigger coil 44 provides an engine input signal substantially representative of engine position and/or speed to ignition module 14 . According to the particular embodiment presented here, the trigger coil 44 is positioned towards the end of the laminated strut 62 and adjacent to the transformer 48 . However, the trigger coils can also be arranged at different positions on the laminations. For example, contrary to the arrangement shown here, the trigger coil and charging coil could be arranged on a single leg of the lamination. Trigger coil 44 may also be omitted, with ignition module 14 receiving an engine input signal from charge coil 42 or other means.

Transformer 48 uses a pair of tightly coupled windings 68 and 70 to generate a high voltage ignition pulse that is delivered via ignition lead 16 to the spark plug. Like the charge and trigger coils described above, the primary and secondary windings of the transformer 48 surround one leg of the lamination 40 , in this case leg 62 . As with any step-up transformer, the primary winding 68 has fewer turns of wire than the secondary winding 70 which has more turns of finer gauge wire. The turns ratio between the primary and secondary windings, as well as other characteristics of the transformer, affects the high voltage and is generally selected based on the particular application in which it is used, as is well known to those skilled in the art.

Ignition module housing 50 is preferably made of rigid plastic, metal or some other material and is designed to surround and protect components of ignition module 14 . The ignition module housing has several openings that allow the lamination legs 60 and 62, ignition wires 16, and electrical connections 18 to protrude, and these openings are preferably closed to prevent moisture and other contaminants from damaging the ignition module. It should be understood that ignition system 10 is but one example of a capacitive discharge ignition (CDI) system that may use ignition module 14 and that numerous other ignition systems and components may be used in addition to those shown here.

ignition module

Referring to FIG. 2 , a schematic circuit diagram of some components of an exemplary ignition module 14 is shown, including a charge coil 42 , a trigger coil 44 , an ignition circuit 46 and a transformer 48 . It should be understood that various changes may be made to this diagram, including the addition, omission, and/or substitution of various electronic components, since this diagram is only intended to provide a general overview of one possible implementation. Ignition circuit 46 may be implemented on a printed circuit board (PCB) or other circuit medium known to those skilled in the art, and is preferably packaged or hermetically enclosed within housing 50 . The ignition circuit 46 utilizes various electronic components, including in this embodiment an electronic processing unit 80 , a first switching device 82 , a second switching device 84 , and an ignition capacitor 86 . As will be described further below, the first switching device 82 may be used as a charge coil clamp switch to implement the throwback charging technique to the ignition capacitor 86, while the second switching device 84 is used to discharge the ignition capacitor 86 to generate the spark.

Electronic processing device 80 executes various electronic instructions related to various tasks, such as ignition timing control, and it may be a microcontroller, microprocessor, application specific integrated circuit (ASIC), or any other suitable type known in the art analog or digital processing devices. In the illustrated embodiment, the electronic processing device 80 is a microcontroller, such as the MSP430 series of microcontrollers produced by Texas Instruments, which runs at 16 MHz and has 8 Kb of memory for storing information like electronic instructions and variables. Typically, the charging coil 42 energizes the electronic processing device via various electronic components including a capacitor 98 for smoothing or otherwise regulating the energy induced in the charging coil. According to the illustrated embodiment, the electronic processing unit 80 includes the following exemplary input/output arrangements: a power input 90 from the charging coil 42 for providing a charging control signal to the first switching device 82 a signal output 92 for providing a charging control signal to the second The switching device 84 provides a signal output 94 for the discharge control signal for receiving a signal input 96 of the engine input signal from the trigger coil 44 via a plurality of signal conditioning circuit components. It should be understood that many circuit arrangements other than those shown in the exemplary embodiments may be used to process, condition or otherwise improve the quality of the signals used therein. Although the engine input signal on input 96 is shown here as being provided serially on a single input, it could alternatively be provided on multiple inputs or according to some other arrangement known in the art. This and other signals are provided. An optional emergency switch 88 for manual override of shutting down the engine may also be coupled to the electronic processing unit 80.

The first switching device 82 is preferably a high voltage solid state switching device that couples the charging coil 42 to ground, the first switching device being controlled by the charging control signal sent from the output 92 . In the illustrated embodiment, the first switching device 82 is shown as a single bipolar transistor, however, other switching devices may also be used. For example, the first switching means 82 could alternatively comprise a single MOSFET, or a pair of transistors connected in a Darlington arrangement; these are commercially available as a single integrated circuit (IC) transistor package. In one embodiment, the first switching device 82 is designed to handle a voltage of at least 300V and a current of at least 1Amp. When the charging control signal turns on the first switching device 82 to conduct, the charging coil 42 is shorted to ground. Conversely, when the charging control signal turns the first switching device 82 off, the short is removed and the charging coil 42 is free to charge the ignition capacitor 86 . According to one embodiment, the first switching device 82 acts as a clamp switch with a minimum voltage rating of 300-350V and a minimum current rating of about 1 Amp, and the firing capacitor 86 has a similar voltage rating and a capacitance of about 0.47 μF. As will be described in further detail below, the electronic processing means 80 controls the charging of the ignition capacitor 86 by controlling the first switching means 82 to produce a regression-type effect during the charging cycle.

The second switching device 84 is preferably a high current solid state switching device, such as a silicon controlled rectifier (SCR) or some other type of thyristor, and is designed to discharge the firing capacitor 86 to create a spark at the spark plug. In this embodiment, the second switching device 84 is part of the energy discharge path including the primary winding 68, the firing capacitor 86 and ground. The second switching device 84 is controlled at its gate by the discharge control signal sent on the output 94 , while the second switching device is preferably designed to accommodate a limited duration current of at least 30 Amp during discharge of the firing capacitor 86 . During normal charging conditions, the second switching device 84 is open so that the electrical energy induced in the charging coil 42 can charge the ignition capacitor 86 .

operation method

Referring to FIGS. 3-4E , a flowchart and timing diagrams are shown to help explain the method 100 of charging the ignition capacitor 86 ; ie, the charging cycle. In step 102 , the electronic processing unit 80 monitors the engine input signal on the input 96 ( FIG. 4A ) to obtain a reading of the position and/or speed of the engine. The engine input signal is shown as a pulse train and is sensed by trigger coil 44 as magnetic element 32 rotates through laminations 40 . At a predetermined point, for example at time t ₀ , the electronic processing device 80 sends a charging control signal to the first switching device 82 ( FIG. 4B ), which turns the first switching device 82 on, see step 104 . It should be appreciated that the time _t0 can be detected in various ways, including counting it as an amount of time after the preceding pulse train of the engine input signal. When the first switching device 82 is on, it provides a low impedance path to ground for the charging coil 42 ; effectively shorting the charging coil so that current induced in the coil can flow through the closed switching device 82 to ground. This is illustrated in FIG. 4C , which shows a rapid increase in charging coil current during the moment after the first switching device 82 is closed. Due to the short circuit of the charging coil 42, the charging coil does not charge the ignition capacitor 86 during the initial phase of the charging cycle.

The electronic processing unit 80 continues to monitor the engine input signal ( FIG. 4A ) or some other suitable indicator, so that at time t ₁ the electronic processing unit 80 opens the first switching device 82 , see step 106 . For ease of explanation, the time period between _t0 and _t1 is referred to as the first phase of the charge cycle, although earlier charge cycle phases may exist. According to one embodiment, the engine input signal is analyzed for a trip point, and once sensed, the electronic processing device 80 opens the first switching device 82 via the charge control signal. It should be appreciated that there are many ways of sensing this break point. For example, trip point 120 may simply correspond to a predetermined signal level y ₀ in the engine input signal. The disconnect point may correspond to a point 122 at a predetermined percentage of the peak signal level of the engine input signal (e.g., 70% of the peak signal level); in this case, the disconnect point 122 occurs at the peak signal level After flat. Alternatively, the disconnect point 124 may correspond to a point on the engine input signal that occurs an amount of time _x0 after some known reference point, such as the peak signal level (e.g., 1 ms after the peak signal level ), regardless of the engine input signal level. Of course, it should be understood that the above examples are only a few possible methods of determining the break point, as other methods may also be used.

When the first switching device 82 is open, a high current level flows from the charging coil 42 through the switching device 82 to ground. A sharp change or interruption in the current flow through the charge coil 42 causes a regression type event in the ignition module 14 . In other words, when the first switching device 82 is opened (open circuit), the current flow through the charging coil 42 is interrupted (FIG. 4C), which results in a destruction of the magnetic field. This disrupted magnetic field in turn produces a high voltage output that is redirected and applied to the firing capacitor 86 according to a throwback charging technique. This is evident in FIG. 4D , where firing capacitor 86 is rapidly charged to elevated voltage level 130 .

Due to this arrangement, a single charging coil 42 can generate sufficient current at higher engine speeds (due to the relatively low inductance and low resistance of the charging coil 42 ) and can provide sufficient current to capacitor 86 at lower engine speeds. voltage (this is mainly due to the high voltage generated during the homing event). Some prior art ignition modules accommodate the high voltage demands at low engine speeds simply by increasing the number of windings, or turns, in the coil; however, increasing the number of turns generally increases the inductance and resistance of the charge coil, resulting in Current cannot be efficiently generated at high engine speeds. In other words, the ignition module described herein meets the charging needs at low engine speeds without compromising the performance of the charging coil at high speeds. Throughout the remainder of the charging cycle, switching devices 82 and 84 are maintained in the "off" state so that firing capacitor 86 is fully charged. For ease of explanation, the time period between _t1 and _t2 is referred to as the second phase of the charging cycle, although there may be additional, intermediate phases between it and the first phase.

While the ignition capacitor 86 is charging, the electronic processing unit 80 utilizes one or more signal inputs, such as an engine input signal, to determine a desired ignition timing, see step 108 . As is well known to those skilled in the art, step 108 may utilize one of a number of different methods and techniques for determining ignition timing, including those disclosed in U.S. Patent No. 7,000,595, which is incorporated herein in its entirety as refer to. It is not necessary to use a particular method or technique to calculate the ignition timing. Once the ignition timing is calculated, the electronic processing device 80 sends a discharge control signal to the second switching device 84 according to the calculated timing (which usually reflects a certain timing advance or delay relative to the top dead center position of the piston), see step 110. At time _t2 , the discharge control signal (FIG. 4E) turns on or triggers the second switching device 84 so that it rapidly discharges the ignition capacitor 86 through the primary winding 68, which induces a high voltage ignition pulse in the secondary winding 70. The ignition pulse is sent to the spark plug and arcs across the spark gap, which ignites the air/fuel mixture and starts the combustion process. If the emergency switch 88 is activated at any time during circuit operation, the electronic processing unit 80 generally prevents the delivery of an ignition pulse to the spark plug.

The description given above is only a description of one possible embodiment for implementing the method 100 . Various modifications of this exemplary method may be made and alternatively may be used. For example, the first switching device 82 is particularly useful when used as a current clamping switch during low engine speeds. During the low rotational speeds of the charging cycle, the charging coil 42 would otherwise be unable to generate sufficient charging voltage for the ignition capacitor 86 . As such, the method 100 may need to be modified to check and see when the engine exceeds a predetermined speed, eg 6000 RPM, at which point a normal uninterrupted charge cycle (no regression) can be used. When the engine is running at a higher RPM than the predetermined RPM, it is usually not necessary to have the regression effect described above, as usually the charging coil itself will generate sufficient voltage.

Turning to FIG. 5, another ignition module 214 is shown that can be used in the ignition system of FIG. 1, however, this embodiment further includes an ignition circuit 246 with a current sense feedback component to determine when to open the first switch Device 282. As before, the first switching means 282 provided in a Darlington arrangement may be a bipolar transistor, or some other type of switch known in the art. Because of the similarity to the ignition circuit 46, the following discussion mainly focuses on some relevant parts of the ignition circuit 246; repeated discussions on the same components are omitted. As before, at the beginning of the charging cycle, the first switching device 282 is turned on to short-circuit the charging coil 42 through the switching device. The current sense input 278 is connected between the current carrying terminal of the first switching device 282 and the ground resistor 276 and provides a current feedback signal representative of the short circuit current flowing through the charging coil 42 to the electronic processing device 280 .

As will be appreciated by those skilled in the art, the arrangement shown in FIG. 5 acts as a voltage divider so that current sense input 278 can provide a current feedback signal to electronic processing device 280 representative of the current flowing through resistor 276, The current flowing through the resistor 276 represents the current flowing through the charging coil 42 . In contrast to the aforementioned engine input signal, the electronic processing device 280 utilizes this current feedback signal to determine when to open the first switching device 280 and initiate a homing event. As before, once the switching device 282 is opened and the corresponding magnetic field in the charging coil 42 is destroyed, the regression effect dumps the high voltage charge to the firing capacitor 286 and continues the charging sequence. Specific techniques for analyzing the current feedback signal and determining the break point may include those previously mentioned (e.g., predetermined signal level, percentage of peak signal level, time after a certain reference point, etc.), and Other methods known in the art. Other types of feedback may also be utilized, including feedback indicative of current flowing through other components of the ignition module 214 .

Referring to FIG. 6 , another exemplary ignition module 314 is shown, however, this embodiment includes one or more additional electronics 320 that are also energized by the charging coil 42 and controlled by the processing electronics 380 . The upper half of the ignition module 314 including the first switching device 382, the second switching device 384, the ignition capacitor 386, etc. may be similar to the previously described embodiments. Additionally, the ignition module 314 may also include circuitry to drive an additional electronic device 320 ; in this example, the additional electronic device 320 is an air-fuel ratio control solenoid. However, it should be understood that other electronic devices may be used in addition to or in place of the solenoid; examples include additional electronic processing devices, electronic motor controllers, electric actuators, electronic throttle adjusters, etc. Additionally, these additional electronics may be internal or external to circuitry 346 .

Referring back again to FIG. 4C , the waveform representing the charge coil current includes a negative portion where the polarity in the charge coil 42 is reversed. The ignition module 314 can utilize these polarity reversal periods to charge an energy storage device 322 , such as an electrolytic capacitor or battery. Once properly charged, the energy storage device 322 can provide energy to additional electronic devices 320 . Certain electronic devices, like solenoids, may require a higher amount of power (typically in the 0.5 watt range) than is typically required by firing capacitor 386 . As previously mentioned, the charging coil 42 utilizes a low impedance/low resistance construction for higher current and/or power needs. More information on solenoids for controlling the air-fuel ratio can be found in the aforementioned US Patent No. 7,000,595.

Tests have shown that the ignition systems, modules and methods described herein can significantly increase or otherwise improve spark ignition voltage at lower engine speeds and power output at higher engine speeds. The power output of the 2-stroke single-cylinder spark ignition engine using the ignition module of the present invention is significantly increased in the lower engine speed range of about 300RPM to 3500RPM, especially in the range of about 300RPM to 2500RPM. Also, the same ignition module demonstrated improved power output at high engine speeds in the 8000RPM range and beyond, especially in the range of approximately 8000RPM to 11000RPM. Some of these results are presented in Figure 7, which shows engine speed (RPM) on the horizontal or x-axis and ignition spark output ( KV) curve relationship.

According to FIG. 7, the ignition module of the present invention provides several desirable attributes compared to conventional prior art capacitive discharge ignition systems. First, in the lower speed range from about 300 RPM to 2500 RPM (this engine speed range belongs to 2-stroke engines), the ignition module of the present invention produces a significantly higher ignition spark output voltage. Second, the ignition spark output voltage produced by the above-mentioned ignition module is significantly higher in the higher speed range from about 8000 RPM to 11000 RPM. Third, the ignition module improves ignition spark output over a wide engine operating region from approximately 400 RPM to 11,000 RPM. Fourth, the ignition modules disclosed above are capable of providing sufficient power to additional electronics, such as solenoids, from the same charge coil that produces an improved ignition spark output. Of course, these are only the desired characteristics of the ignition module described above, which may also include other potential and unique advantages.

Those skilled in the art can believe and understand that a 4-stroke single-cylinder internal combustion engine with the above-mentioned ignition module will also have similarly significantly higher power output and similarly significantly increased voltage output characteristics. Especially when the 4 stroke engine is running in the range of about 150RPM to 5000RPM. It is believed that this 4-stroke engine will also have significantly increased power and voltage output in the low to mid speed range of about 150 RPM to 2000 RPM and in the high speed range of about 4000 RPM to 5000 RPM.

It should be understood that the above description is not intended to limit the present invention, but to illustrate one or more preferred embodiments of the present invention. The invention is not limited to the specific embodiments disclosed herein, but only by the following claims. Furthermore, the discussion contained in the foregoing specification relates to specific embodiments and should not be construed as limitations on the scope of the invention or definitions of terms used in the claims, unless a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiments will become apparent to those skilled in the art. All such other embodiments, changes and modifications are intended to come within the scope of the appended claims.

As used in the specification and claims, the terms "for example", "for example", "exemplary", and the verbs "comprise", "have", "comprise" and their other verb forms, when Where they are used in conjunction with a list of one or more components or other items, each of them is to be construed as open-ended, that is, the list is not considered to be exclusive of other additional components or items. Other terms should be interpreted using their broadest reasonable meaning, unless their context requires a different interpretation.

Claims (12)

1. An ignition module for a capacitor discharge ignition (CDI) system, comprising: a charge coil mounted in the ignition module to induce electrical energy in response to one or more rotating magnetic elements; an ignition capacitor coupled to the charging coil to receive electrical energy from the charging coil; a first switching device coupled to the charging coil; a second switching device coupled to the firing capacitor; and electronic processing means coupled to the first switching means to provide a charge control signal thereto, the electronic processing means coupled to the second switching means to provide a discharge control signal thereto, wherein activation of the first switching means A low impedance path is created between ground and ground. 2. The ignition module of claim 1, wherein the charging coil has an inductance of about 2-10 mH inclusive; a resistance of about 10-50Ω inclusive, which facilitates the ignition module to perform a regressive charging technique. 3. The ignition module of claim 1, wherein the first switching means includes a first current carrying terminal coupled between the charge coil and the ignition capacitor, a second current carrying terminal coupled to ground, and a second current carrying terminal coupled to the electronic processing means A control terminal receives a charge control signal, wherein turning on the first switching device causes current to flow between the first and second current carrying terminals. 4. The ignition module of claim 1, further comprising additional electronics, wherein the electrical energy induced in the charging coil both charges the ignition capacitor and energizes the additional electronics. 5. The ignition module of claim 1, wherein the electronic processing means turns on the first switching means using the charging control signal during the first phase of the charging cycle, and turns off the first switching means during the second phase of the charging cycle, thereby The ignition capacitor is charged with the electric energy induced in the charging coil using the regressive charging technique. 6. A method of operating an ignition module comprising the steps of: (a) induction of electrical energy in the charging coil; (b) shorting the charging coil during the first phase of the charging cycle so that current flows between the charging coil and ground; (c) interrupting said short circuit during the second phase of the charge cycle, thereby allowing current to flow between the charge coil and the ignition capacitor; (d) Charge the ignition capacitor according to the regression charging technique. 7. The method of claim 6, wherein step (c) further comprises interrupting the short circuit during a second phase of the charging cycle beginning at time t ₁ , where time t ₁ is calculated from an engine input signal. 8. The method of claim 6, further comprising the step of: Determining when the engine exceeds a predetermined engine speed and, if the engine exceeds the predetermined engine speed, replacing the drop-back charging technique with an uninterrupted charging cycle. 9. The method of claim 6, wherein step (c) further comprises interrupting the short circuit during a second phase of the charging cycle, wherein the moment at which the second phase of the charging cycle begins is calculated from a current feedback signal, The current feedback signal represents the short-circuit current flowing through the charging coil. 10. The method of claim 6, wherein the method is used in a 2-stroke light duty internal combustion engine, and at least one of steps (b) or (c) is performed when the internal combustion engine is operating in a lower speed range of about 300 RPM to 2500 RPM . 11. The method of claim 6, wherein the method is used in a 4-stroke light duty internal combustion engine, at least one of steps (b) or (c) is performed when the internal combustion engine is operating in a lower speed range of about 150 RPM to 2000 RPM . 12. The method of claim 6, further comprising the step of: The additional electronics are energized with the electrical energy induced in the charging coil, which can both charge the ignition capacitor and energize the additional electronics.

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